The present invention relates generally to poultry and small animals watering devices and, more particularly, to nipple drinker systems for poultry.
The invention of this application represents an improvement upon the invention described in co-pending U.S. Pat. application Ser. No. 07/420,683, filed Oct. 11, 1989. That prior invention relates generally to an improved arrangement for trigger drinkers wherein a metering pin is employed to regulate the flow of fluid upstream from the ball valve arrangement in the typical nipple drinker. The present invention provides refinement and improvement in specific structure of metering pins for such drinkers.
Prior nipple drinkers (also commonly referred to as trigger drinkers) such as the model 300 nipple drinker marketed by Ziggity Systems, Inc. several years ago demonstrated that nipple drinkers can be used successfully to improve the growing conditions of poultry by varying the water flow rates to birds as they mature. Specifically, the Ziggity Model 300 drinker provided two types of water flow to the poultry depending upon the method of actuation. Side to side force applied to the actuating pin, such as is typically used by day-old chicks and young birds, produced a relatively low flow rate sufficient to meet the demands of birds of that age. It is believed that this lower flow rate was achieved because in side to side motion the actuating (or "trigger") pin, which was in that model the flow restricting pin, was partially blocking the flow through the drinker outlet in combination with the ball valve element. On the other hand, as the birds matured and needed more water they demonstrated a tendency to lift the pin more often with vertical force. It was found the vertical actuation of the trigger pin provided a greater rate of flow, presumably because there was less obstruction in the flow passageway through the drinker outlet. Another factor in the difference in flow rates was that the water pressure was gradually increased as the birds matured, typically from 3 inches to less than 12 inches of water pressure.
As indicated in the above-referenced patent application, however, experience has shown that in some circumstances the Ziggity Model 300 nipple drinker did not maintain its optimum performance forever. Particularly, over a period of several years there was a possibility that the opening at the outlet of the nipple drinker would become enlarged as a result of wear. Further, in those instances where the water supply is not properly filtered or where sediments and contaminates result in the water supply system (possibly because of excessive or combinate use of water additives by growers) valve operation could be detrimentally affected. Further, in nipple drinkers produced by other sources employing metal seats and metal trigger pins it has been reported that an additional factor contributing to wear at the nipple drinker outlet is the effect of electrolysis between the metal surfaces. Typically, as the drinker outlet increased in size the incidents of leakage and excessive water flow also increased.
In response to the gradual enlargement of the nipple drinker outlet, it has been suggested to decrease the water pressure to prevent excessive leakage and excessive flow of water to the poultry. However, this solution has been found useful only for a limited period of time and even if continued the water pressure would need frequent adjustment throughout the useful life of the nipple drinker. The typical grower would, thus, need to be constantly alert to the condition of his equipment so as to maintain optimum conditions. It is more desirable however, to create a system that is maintenance free throughout its useful life without decreasing the length of that useful life. Thus, the thrust of the above-referenced patent application was to shift the flow control location to the inlet of the nipple drinker through the use of a metering pin which moved vertically in response to either type of actuating force.
While the metering pin of the above-described patent application has performed satisfactorily in many instances, it has been discovered that performance can be improved even further through the use of the present invention. With a single stage metering pin only a single type of flow rate is typically observed because the net affect of any type of movement of the trigger pin is to provide vertical movement of the metering pin. Thus, the total volume of water supplied is proportional to the water pressure in the same manner at all stages of poultry growth. In certain instances, however, it is desirable still to provide a lesser volume of water for day-old chicks than this proportional relationship would permit without adversely affecting the water supply to those birds as they get older. Prior metering pins have used greater water pressures, for example, to increase the flow rate to supply birds with adequate water during hot weather. However, such increased pressures also increase the potential for leakage and require greater force to open the nipple drinker valve. Where leveraged actuation of the trigger pin against the ball of the nipple drinker valve is employed, as described in U.S. Pat. No. 4,491,088, this can often still be readily achieved even by day-old chicks. However, it has been found to be advantageous to decrease the actuation force necessary for day-old chicks to obtain water as much as possible. It has also been suggested that manufacturing costs of nipple drinkers can be decreased by employing flat-headed trigger pins, without the recess used for leverage actuation. Further, it has also been suggested that various different plastic and rubber seat compositions can be employed to provide greater sealing and improved resistance to chemical deterioration, especially in watering systems needing frequent flushing at relatively high pressures. Both of these types of arrangements are believed to be able to result in a higher necessary actuation force in some circumstances than certain day-old chicks, particularly those from spent hens, are able to provide. Thus, it is desirable to provide a metering pin arrangement which does not require increased pressure to achieve greater flow rate for day-old chicks. On the other hand, it is desirable to provide for greater water volume to be available to older birds using the same watering system.
It is an object of the present invention to provide an improved nipple drinker.
Another object of this invention is the provision of an improved nipple drinker which includes a metering pin which optimizes flow rates at reduced pressures.
These and other advantages of the present invention are achieved by the provision of a metering pin having two portions of different external configuration, each of which portions are insertable into the fluid flow path for restricting fluid flow under different actuating conditions. These two portions can be dimensioned to be readily retrofit into various existing nipple drinkers according to the configuration of the drinker inlet. The specific dimensions of each portion relative to the drinker inlet can be selected according to desired flow rates at different levels of poultry growth.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.